Growth of cells superinoculated onto irradiated and nonirradiated confluent monolayers.
We prepared confluent monolayers of normal BALB/c 3T3 cells and compared differences in the growth of four types of cells superinoculated onto these nonirradiated and irradiated monolayers. The test cells were normal BALB/c 3T3 A31 cells, a squamous cell carcinoma from a human esophageal cancer (KSE-1), human fetal fibroblasts, and V-79 cells from Chinese hamster lung fibroblasts. Cell growth was checked by counting the cell number, determining [3H]thymidine incorporation and assessing colony formation. We found that on nonirradiated monolayers, colony formation of human fetal fibroblasts and normal BALB/c 3T3 cells was completely inhibited. On irradiated cells, test cells did exhibit some growth. KSE-1 cells, which had a low clonogenic efficiency on plastic surfaces, formed colonies on both irradiated and nonirradiated cells. On these monolayers, the clonogenic efficiency of V-79 cells was also higher than that on plastic surfaces. We conclude that the nonirradiated monolayer of BALB/c 3T3 cells completely inhibits the growth of superinoculated normal BALB/c 3T3 and human fetal fibroblasts, while on the other hand, they facilitate the growth of neoplastic KSE-1 and V-79 cells by providing a surface for cell adherence and growth, without affecting the presence of normal cells in co-cultures.
Matsuoka
H
H
Department of Surgery, Kyushu University, Fukuoka, Japan.
Ueo
H
H
Sugimachi
K
K
D000818:Animals; D002455:Cell Division / Q000528:radiation effects*; D002461:Cell Line, Transformed; D006224:Cricetinae; D003412:Cricetulus; D005347:Fibroblasts / Q000166:cytology*; D006801:Humans; D051379:Mice; D008807:Mice, Inbred BALB C; D014407:Tumor Cells, Cultured / Q000528:radiation effects